... 3mmSurface finish : automatic electro-static powder coating ,anti-collision ,anti-shedding ,anti-corrosion etc .Lock system :1.multi cross shafts,using solid core ... :while close the box , automatic locking system will lock the box immediately .3.Automatic re-locking function, when ... improper way or force ,box will re-lock itself.4.Password lock ,mechanical lock ,which is drill-proof ,smash-proof , ...